Restriction enzymes selection

Restrictions for the substrates of the transketolase-catalyzed reaction only arise from the stereochemical requirements of the enzyme. The acceptor aldehyde must be formaldehyde9,20, glycolaldehydel6,17 or a (R)-2-hydroxyaldehyde10,17. The donor ketose must exhibit a (3(7,4 R) configuration10. The enzyme selectively adds the hydroxyacetyl moiety to the Re-face of the acceptor aldehyde leading to a 3(7 configuration of the products. 

PUTTING YOUR DNA INTO A VECTOR Vectors are specialized pieces of DNA used to move other pieces of DNA around. Modern vectors are usually either bacterial plasmids or viral genomes. The act of isolating your DNA in the first place usually involves putting it into a vector and then selecting the vector that has your DNA in it. DNA pieces (called inserts when they are placed in a vector) are usually placed in vectors using restriction endonucleases. The vector is cut with two restriction enzymes of different specificity (Fig. 6-3). This removes a... 

Obtain samples of selected restriction enzymes and reaction buffer (supplied with enzymes). Also obtain a DNA sample, either a viral (lambda) or bacterial plasmid. 

Mutation screening methods involve testing for specific (previously selected) mutations in a gene. This approach is relatively inexpensive and may be useful for disorders that are caused by one or few common mutations. It is important to take the origin of the patient into consideration, since the frequency of mutations differs markedly between populations. As an example for such a method we discuss restriction enzyme analysis in more detail in this chapter. 

The objective of the experiment is to evaluate the action of restriction enzymes on bacterial plasmids, A phage DNA, or viral DNA. The DNA will be incubated under the appropriate conditions with selected restriction enzymes. The reaction mixtures will be subjected to agarose gel electrophoresis in order to determine the number and molecular size of the restriction fragments. 

Recognition Sequences and Cutting Sites of Selected Restriction Enzymes... 

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